docs: def add_analysis_attributes(self, group_name, attrs, clear=False):
          """ Add attributes on the group or dataset specified.
          
          :param group_name: The name of the group (or dataset).
          :param attrs: A dictionary representing the attributes to add.
          :param clear: If set, any existing attributes will be cleared.
          
          The specified group name can be any existing path (relative to the
          "Analyses" group. It can be a group or a dataset.
          """
          self.assert_writeable()
          group = 'Analyses/{}'.format(group_name)
          self._add_attributes(group, attrs, clear)